Form is one type of the most frequently used document in the services business. There is often a need for embedding information in a paper form. The information could be used for various purposes, for example, verification, tampering prevention and process control. One application includes the mailing of forms to the general population as surveys. Currently, each of the pages on these forms may have a bar code which connects the form and page to an individual to whom the form was sent for completion. According to the disclosed methods and systems of embedding/extracting information, the bar code is eliminated by embedding the information in invisible or aesthetically pleasing marks.
While the technology described in this disclosure is applied to lines on forms, it can also be used for other type of documents.
Related art exists on encoding information via adding tiny dots/marks, see U.S. Pat. No. 8,224,019, by Fan et al., issued Jul. 17, 2012, entitled “EMBEDDING INFORMATION IN DOCUMENT BLANK SPACE”; U.S. Pat. No. 8,243,982, by Fan et al., issued Aug. 14, 2012, entitled “EMBEDDING INFORMATION IN DOCUMENT BORDER SPACE”; U.S. Pat. No. 7,792,324, by Fan et al., issued Sep. 7, 2010, entitled “SYSTEM AND METHOD FOR EMBEDDING MINIATURE SECURITY MARKS”; and U.S. Pat. No. 7,292,710, by Fan et al., issued Nov. 6, 2007, entitled “SYSTEM FOR RECORDING IMAGE DATA FROM A SET OF SHEETS HAVING SIMILAR GRAPHIC ELEMENTS”. Each of the above-cited methods of encoding information has its own trade-off with respect to channel capacity, visibility, robustness, and complexity of encoding/decoding.